A comparison of pethidine and remifentanil patient-controlled analgesia in labour

We conducted a double-blind randomised controlled trial comparing the efficacy of analgesia during labour of remifentanil and pethidine. Nine women were randomised to receive an i.v. bolus of remifentanil 0.5 microg.kg(-1)with a lockout period of 2 min and eight women were randomised to receive a bolus of pethidine 10 mg with a lockout period of 5 min. A visual analogue scale (VAS) scoring system was used to assess the level of pain hourly throughout the first and second stages of labour and a score was recorded within half an hour of delivery for the level of pain overall throughout labour (post delivery score). The study was terminated after 17 subjects, on agreement with the local ethics committee, due to concern with the poor Apgar scores in the pethidine group. With the data available, we demonstrated significantly lower mean hourly and post delivery VAS scores for pain in the remifentanil group (P < 0.05). The 1 and 5 min Apgar scores were significantly lower in the pethidine group compared with the remifentanil group (P < 0.05). This preliminary study suggests that remifentanil may have a use as patient-controlled analgesia for women in labour.